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Dutch lighting Innovations (DLI) develops and manufactures supplemental lighting systems for the global greenhouse industry. They’ve recently made the decision to step into the home and hobby markets, too. Focusing on reliable, low-maintenance products built from high quality components and to exacting standards, a cursory glance at their lighting fixtures is enough to see how 25 years of industry experience translates  into an exceptional high level of design.

A Philips OEM, DLI is working with The Growers Wholesales to distribute their products in the UK. We sat down with Pepijn Looijaard to get to grips with The JOULE-Series light fixtures and DLM Series controllers.

There’s nothing better than to grow your own produce and plants. Everybody should be doing it.

Dutch Lighting Innovations is a well established company, but for people who may not have heard of you; what led you to create your own range of horticultural lighting equipment?

Ton ten Haaf and I have been working in horticultural lighting for a long time already. After studying Physics in Eindhoven, I joined Philips. After Philips decided not to make fixtures for horticulture anymore, but instead only focus on making components for fixtures, Ton and I decided to start our own company in which we completely focus on making light as efficient as possible.


You’ve previously operated heavily in the commercial sector; what brought you to the domestic and hobby markets?

Plants are plants. We figured out how to successfully make plant lighting for flowers and tomatoes on large scales. We wanted to have the general public be able to grow their own plants too. There’s nothing better than to grow your own produce and plants. Everybody should be doing it.




We’ve seen lots of similar lighting fixtures released in recent years; what sets the JOULE-Series apart from the competition?

I’ve seen them come and go as well. Now every ballast builder or lamp manufacturer calls himself a fixture-manufacturer, but making a fixture is a different trade.

The lamp and the ballast are the heart of the fixture, but the reflector is the soul of the fixture. We developed lighting as a means for production. We made sure that the reflector was developed to be highly efficient, but also entirely uniform. We’ve created an open-style reflector that will show no hotspots on the plant, even when the distance between the reflector and the plants is as low as 90 centimeters (3ft). The reason no hotspots appear is because the light is distributed evenly over the canopy instead of focused downward like most fixtures on the market. The fixture itself is made to be as compact as possible, with a built in spirit level, to assure a perfectly even light spread. We also developed an easy to use controller that can take up to 2000 lights per unit on 4 different zones.

So, if our readers have invested in a generic fixture are there any tell-tale signs that the product might be substandard?

Any light fixture will help growing plants. A candle would even help growing plants. We are focused on efficiency and bringing light efficiently towards the plants. We’ve researched the best spectrum for growing and made sure to supply the most efficient lamps with our JOULE-Series fixtures. We’ve focused on temperature management of both lamp and electronics to assure a long lifespan.

If you combine spectrum, energy-use and uniformity, it could mean replacing generic fixtures with the JOULE-Series could make your grow about 50% more efficient and the quality of the plants would be remarkably better.

horticultural light, grow light, Dutch lighting Innovations, DLI JOULE series


What can you tell us about your DLM-4 Zone Controller, how is it different from existing controllers on the market?

The DLM-4 Zone Controller is specially designed to set up a Daily Lighting Management system for your Dutch Lighting Innovations JOULE-Series fixtures. The DLM-4 Zone Controller can be connected to up to 4 separate zones of DLI lighting fixtures. Each controller can control up to 2000 lights. Once connected to the fixtures, the controller will monitor and control the lights using a digital time-clock. Up to 4 separate temperature sensors can be connected that will measure the temperature of up to 4 zones / growing areas. The user can select to dim the lights if the temperature goes above their chosen set-point, or to turn the lights off.  Each fixture comes with a cable-set so that it can be connected to the controller. In the coming months we will be launching a full Climate Control System. In addition to the lighting, it can also control CO2, Temperature and Humidity.

horticultural light, grow light, Dutch lighting Innovations, DLI JOULE series

Tell us about your hashtag campaign, #FLOWERSONLY; what’s the thinking behind it?

Our reflector has been designed specifically for flowering crops when the light is hung from a specific height. Unlike others that have been designed for foliage and hung from a very large height. In the end, isn’t it what growlights are made for: for flowers only?


People talk a lot about Philips’ lamp technology being the best; are JOULE-Series fixtures compatible with the Philips range? How does your own brand of lamps compare?

DLI is a Philips OEM (Original Equipment Manufacturer) which means that our fixture has been tested thoroughly by Philips. We use Philips gear a lot in horticulture projects because the Philips lamps have been designed specifically for greenhouses with a lot of daylight. For home growing we’ve decided to cooperate with a different manufacturer of lamps. We did a lot of testing until we were sure we had the right spectrum for indoor growing.


horticultural light, grow light, Dutch lighting Innovations, DLI JOULE series


We noticed ‘BrightShine Reflector Wipes’ on your website; it’s not a product we’re familiar with. How important is it that people clean their reflectors properly?

The open style reflector has a lot of advantages. One of them is that dirt doesn’t really burn into the material. Also because we built a chimney-effect into it. Hot air rises and is vented out of the reflector taking dirt-particles along with it. Reflectors, however, have to be cleaned. When using BrightShine wipes, the reflector will go back to 99% of the initial reflectance. The material of closed style reflector gets really hot. Because of this, dirt will burn into the material. The BrightShine wipes are used on closed-style reflectors to wipe off surface dirt and dust, but it can’t restore the original reflectance.


Who is distributing your JOULE-Series light fixtures in the UK?

The Growers Wholesale proved to be the perfect fit for us; they’re the fastest growing wholesaler in the UK and it’s no surprise. Their sales team are out on the road really putting the work in; they’ve clearly got a great working relationship with retailers across the UK and a number of fantastic brands on board like Canna, Future Harvest Development and Environmental Climate Control.


If you could give one piece of advice to people, what would it be?

Don’t just buy lights, instead buy plant specific lighting. Quality light will bring quality plants.


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